Diversity of the HIV-1 Long Terminal Repeat Following Mother-to-Child Transmission

AbstractA study of the human immunodeficiency virus Type 1 (HIV-1) 5′ long terminal repeat (LTR) was performed to determine the extent of variation found within the LTR from 19 mother–infant pairs in Tanzania and to assess whether the LTR is useful in distinguishing maternal sequences that were transmitted to infants. HIV-1 subtypes A, C, and D as well as intersubtype recombinant LTR sequences were detected in mothers and infants. The LTR subtype was 100% concordant between mothers and their infants. Diversity calculations showed a significant reduction in LTR variation in infants compared to their mothers. However, the overall magnitude of LTR variation was less than that found in the env gene from the same individuals. These data suggest a selective constraint active upon the 5′ long terminal repeat that is distinct from immune selective pressure(s) directed against HIV-1 structural genes. Detection of maternal LTR variants that were transmitted to infants may yield important information concerning nonstructural determinants of HIV-1 transmission from mother to infant

Recommendations for evaluation and management of bone disease in HIV

Thirty-four human immunodeficiency virus (HIV) specialists from 16 countries contributed to this project, whose primary aim was to provide guidance on the screening, diagnosis, and monitoring of bone disease in HIV-infected patients. Four clinically important questions in bone disease management were identified, and recommendations, based on literature review and expert opinion, were agreed upon. Risk of fragility fracture should be assessed primarily using the Fracture Risk Assessment Tool (FRAX), without dual-energy X-ray absorptiometry (DXA), in all HIV-infected men aged 40-49 years and HIV-infected premenopausal women aged ≥40 years. DXA should be performed in men aged ≥50 years, postmenopausal women, patients with a history of fragility fracture, patients receiving chronic glucocorticoid treatment, and patients at high risk of falls. In resource-limited settings, FRAX without bone mineral density can be substituted for DXA. Guidelines for antiretroviral therapy should be followed; adjustment should avoid tenofovir disoproxil fumarate or boosted protease inhibitors in at-risk patients. Dietary and lifestyle management strategies for high-risk patients should be employed and antiosteoporosis treatment initiated

HIV type 1 subtypes among bar and hotel workers in Moshi, Tanzania.

The HIV-1 prevalence among bar and hotel workers in Tanzania suggests they are a high-risk group for HIV-1 infection. We determined the HIV-1 subtype of 3'-p24/5'-p7 gag and C2-C5 env sequences from 40 individuals representing this population in Moshi. Genetic patterns composed of A(gag)-A(env), C(gag)-C(env), and D(gag)-D(env) were found in 19 (48.0%), 8 (20.0%), and 3 (8.0%) samples, respectively. The remaining 10 samples (25%) had different subtypes in gag and env, indicative of intersubtype recombinants. Among these recombinants, two contained sequences from HIV-1 subsubtype A2, a new genetic variant in Tanzania. Five bar and hotel workers may have been infected with viruses from a common source, based on phylogenetic analysis. The information obtained by surveillance of HIV-1 subtypes in a high-risk population should be useful in the design and evaluation of behavioral, therapeutic, and vaccine trial interventions aimed at reducing HIV-1 transmission

Epidemic expansion of HIV type 1 subtype C and recombinant genotypes in Tanzania

Human immunodeficiency virus type 1 (HIV-1) subtypes are distributed unevenly across African nations.1 In East and Central African countries such as Uganda, Rwanda, Kenya, and Tanzania, the HIV-1 epidemic has involved two HIV-1 subtypes, A and D. In contrast, HIV-1 subtype C has dominated the rapidly expanding epidemic in Malawi and South Africa.1-3 The relative roles played by virological, behavioral, and host determinants in the epidemic expansion of any particular HIV- 1 subtype are unclear. Characterization of the transmissibility and pathogenic potential of distinct HIV-1 genetic subtypes is currently under investigation in many regions of the world. Careful surveillance of genetic subtypes prevalent in a given population is one particularly important approach to better understand the biological properties of different HIV-1 subtypes. The presence of HIV-1 subtypes A and D in asymptomatic carriers and AIDS patients from several geographical locales in Tanzania has been previously described.4-7 An analysis of samples collected in 1988 showed that 10 of 15 (67%) envelope V3 sequences from Tanzanian samples were found to belong to subtype D. The remaining five samples (33%) belonged to HIV-1 subtype A.4 In Dar es Salaam, vpu and env sequences from 8 of 10 AIDS patients (80%) clustered with subtype D viruses and the remaining 2 (20%) with subtype A.5 A study in northern Tanzania reported that the env-encoded gp41 regions from 12 samples also clustered with HIV-1 subtypes A and D.6 In another report from northern Tanzania, four of eight (50%) envelope sequences sampled encompassing the C2V3 region belonged to subtype A and the other half to subtype D.7 Envelope sequences from HIV-1-infected individuals of Tanzanian origin, but living in Sweden, showed that three of four samples were HIV-1 subtype C and the remaining sample was HIV-1 subtype A.

Herpes simplex virus type 2 infection among bar and hotel workers in northern Tanzania: prevalence and risk factors.

BACKGROUND: Type-specific serological tests have allowed for a better understanding of the epidemiology of herpes simplex virus type 2 (HSV-2) infection in Africa. GOAL: The goal was to determine risk factors for HSV-2 among bar and hotel workers in Moshi, Tanzania. STUDY DESIGN: A cross-sectional study was conducted involving 515 workers in randomly selected bars and hotels in Moshi. RESULTS: The seroprevalence of HSV-2 was 43.5%. Women were more likely to be HSV-2-seropositive than men (age-adjusted OR = 3.8; 95% CI = 2.5-5.8). In multivariate analyses, age was positively associated with HSV-2 in both women and men. HIV-1-seropositive women had a significantly increased risk of HSV-2 infection (adjusted OR = 2.8; 95% CI = 1.5-5.1). Other predictors of HSV-2 were religion and sexual behavior for women and level of education, frequency of alcohol use, and concurrent partners for men. CONCLUSION: The most common genital infection was that with HSV-2. Control of HSV-2 might be an important strategy for HIV-1 infection prevention in this population